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riscv-gcc-1
Commit f8b954fc by Neil Booth Committed by Neil Booth
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cppexp.c (CPP_UMINUS, CPP_UPLUS): New. 

	* cppexp.c (CPP_UMINUS, CPP_UPLUS): New.
	(HAVE_NO_R_OPERAND): Remove.
	(HAVE_VALUE): Remove.
	(op_to_prio): Update.
	(UNARY): Don't alter flags.
	(_cpp_parse_expr): want_value used to indicate whether
	a number or unary operator is expected next.  Distinguish
	unary and binary +/-.
	(op_as_text): Update for unary operators.

From-SVN: r52780
parent 6052bef0
Showing with 95 additions and 83 deletions
gcc/ChangeLog
2002-04-26 Neil Booth <neil@daikokuya.demon.co.uk>
* cppexp.c (CPP_UMINUS, CPP_UPLUS): New.
(HAVE_NO_R_OPERAND): Remove.
(HAVE_VALUE): Remove.
(op_to_prio): Update.
(UNARY): Don't alter flags.
(_cpp_parse_expr): want_value used to indicate whether
a number or unary operator is expected next. Distinguish
unary and binary +/-.
(op_as_text): Update for unary operators.
2002-04-25 Richard Henderson <rth@redhat.com> 2002-04-25 Richard Henderson <rth@redhat.com>
PR c/2161 PR c/2161
......
gcc/cppexp.c
...@@ -48,9 +48,12 @@ struct op ...@@ -48,9 +48,12 @@ struct op
HOST_WIDEST_INT value; /* The value logically "right" of op. */ HOST_WIDEST_INT value; /* The value logically "right" of op. */
}; };
/* There is no "error" token, but we can't get comments in #if, so we can /* Token type abuse. There is no "error" token, but we can't get
abuse that token type. */ comments in #if, so we can abuse that token type. Similarly,
create unary plus and minus operators. */
#define CPP_ERROR CPP_COMMENT #define CPP_ERROR CPP_COMMENT
#define CPP_UPLUS (CPP_LAST_CPP_OP + 1)
#define CPP_UMINUS (CPP_LAST_CPP_OP + 2)
/* With -O2, gcc appears to produce nice code, moving the error /* With -O2, gcc appears to produce nice code, moving the error
message load and subsequent jump completely out of the main path. */ message load and subsequent jump completely out of the main path. */
...@@ -454,10 +457,9 @@ same way as the ultra-low priority end-of-expression dummy operator. ...@@ -454,10 +457,9 @@ same way as the ultra-low priority end-of-expression dummy operator.
The exit code checks to see if the operator that caused it is ')', and The exit code checks to see if the operator that caused it is ')', and
if so outputs an appropriate error message. if so outputs an appropriate error message.
The parser assumes all shifted operators require a right operand The parser assumes all shifted operators require a left operand unless
unless the flag NO_R_OPERAND is set, and similarly for NO_L_OPERAND. the flag NO_L_OPERAND is set. These semantics are automatic; any
These semantics are automatically checked, any extra semantics need to extra semantics need to be handled with operator-specific code. */
be handled with operator-specific code. */
#define FLAG_BITS 8 #define FLAG_BITS 8
#define FLAG_MASK ((1 << FLAG_BITS) - 1) #define FLAG_MASK ((1 << FLAG_BITS) - 1)
...@@ -466,10 +468,8 @@ be handled with operator-specific code. */ ...@@ -466,10 +468,8 @@ be handled with operator-specific code. */
#define EXTRACT_FLAGS(CNST) ((CNST) & FLAG_MASK) #define EXTRACT_FLAGS(CNST) ((CNST) & FLAG_MASK)
/* Flags. */ /* Flags. */
#define HAVE_VALUE (1 << 0) #define NO_L_OPERAND (1 << 0)
#define NO_L_OPERAND (1 << 1) #define SHORT_CIRCUIT (1 << 1)
#define NO_R_OPERAND (1 << 2)
#define SHORT_CIRCUIT (1 << 3)
/* Priority and flag combinations. */ /* Priority and flag combinations. */
#define RIGHT_ASSOC (1 << FLAG_BITS) #define RIGHT_ASSOC (1 << FLAG_BITS)
...@@ -501,8 +501,8 @@ op_to_prio[] = ...@@ -501,8 +501,8 @@ op_to_prio[] =
/* NOT */ UNARY_PRIO, /* NOT */ UNARY_PRIO,
/* GREATER */ LESS_PRIO, /* GREATER */ LESS_PRIO,
/* LESS */ LESS_PRIO, /* LESS */ LESS_PRIO,
/* PLUS */ UNARY_PRIO, /* note these two can be unary */ /* PLUS */ PLUS_PRIO,
/* MINUS */ UNARY_PRIO, /* or binary */ /* MINUS */ PLUS_PRIO,
/* MULT */ MUL_PRIO, /* MULT */ MUL_PRIO,
/* DIV */ MUL_PRIO, /* DIV */ MUL_PRIO,
/* MOD */ MUL_PRIO, /* MOD */ MUL_PRIO,
...@@ -525,7 +525,10 @@ op_to_prio[] = ...@@ -525,7 +525,10 @@ op_to_prio[] =
/* EQ_EQ */ EQUAL_PRIO, /* EQ_EQ */ EQUAL_PRIO,
/* NOT_EQ */ EQUAL_PRIO, /* NOT_EQ */ EQUAL_PRIO,
/* GREATER_EQ */ LESS_PRIO, /* GREATER_EQ */ LESS_PRIO,
/* LESS_EQ */ LESS_PRIO /* LESS_EQ */ LESS_PRIO,
/* EOF */ FORCE_REDUCE_PRIO,
/* UPLUS */ UNARY_PRIO,
/* UMINUS */ UNARY_PRIO
}; };
#define COMPARE(OP) \ #define COMPARE(OP) \
...@@ -544,8 +547,7 @@ op_to_prio[] = ...@@ -544,8 +547,7 @@ op_to_prio[] =
top->unsignedp = unsigned1 | unsigned2; top->unsignedp = unsigned1 | unsigned2;
#define UNARY(OP) \ #define UNARY(OP) \
top->value = OP v2; \ top->value = OP v2; \
top->unsignedp = unsigned2; \ top->unsignedp = unsigned2;
top->flags |= HAVE_VALUE;
#define SHIFT(PSH, MSH) \ #define SHIFT(PSH, MSH) \
if (skip_evaluation) \ if (skip_evaluation) \
break; \ break; \
...@@ -568,8 +570,7 @@ _cpp_parse_expr (pfile) ...@@ -568,8 +570,7 @@ _cpp_parse_expr (pfile)
There is a stack element for each operator (only), There is a stack element for each operator (only),
and the most recently pushed operator is 'top->op'. and the most recently pushed operator is 'top->op'.
An operand (value) is stored in the 'value' field of the stack An operand (value) is stored in the 'value' field of the stack
element of the operator that precedes it. element of the operator that precedes it. */
In that case the 'flags' field has the HAVE_VALUE flag set. */
#define INIT_STACK_SIZE 20 #define INIT_STACK_SIZE 20
struct op init_stack[INIT_STACK_SIZE]; struct op init_stack[INIT_STACK_SIZE];
...@@ -579,6 +580,7 @@ _cpp_parse_expr (pfile) ...@@ -579,6 +580,7 @@ _cpp_parse_expr (pfile)
int skip_evaluation = 0; int skip_evaluation = 0;
int result; int result;
unsigned int lex_count, saw_leading_not; unsigned int lex_count, saw_leading_not;
bool want_value = true;
/* Set up detection of #if ! defined(). */ /* Set up detection of #if ! defined(). */
pfile->mi_ind_cmacro = 0; pfile->mi_ind_cmacro = 0;
...@@ -589,8 +591,6 @@ _cpp_parse_expr (pfile) ...@@ -589,8 +591,6 @@ _cpp_parse_expr (pfile)
top->op = CPP_EOF; top->op = CPP_EOF;
/* Nifty way to catch missing '('. */ /* Nifty way to catch missing '('. */
top->prio = EXTRACT_PRIO(CLOSE_PAREN_PRIO); top->prio = EXTRACT_PRIO(CLOSE_PAREN_PRIO);
/* Avoid missing right operand checks. */
top->flags = NO_R_OPERAND;
for (;;) for (;;)
{ {
...@@ -603,38 +603,41 @@ _cpp_parse_expr (pfile) ...@@ -603,38 +603,41 @@ _cpp_parse_expr (pfile)
lex_count++; lex_count++;
/* If the token is an operand, push its value and get next /* If the token is an operand, push its value and get next
token. If it is an operator, get its priority and flags, and token. If it is an operator, handle some special cases, get
try to reduce the expression on the stack. */ its priority and flags, and try to reduce the expression on
the stack. */
switch (op.op) switch (op.op)
{ {
case CPP_ERROR: case CPP_ERROR:
goto syntax_error; goto syntax_error;
push_immediate:
case CPP_NUMBER: case CPP_NUMBER:
/* Push a value onto the stack. */ /* Push a value onto the stack. */
if (top->flags & HAVE_VALUE) if (!want_value)
SYNTAX_ERROR ("missing binary operator"); SYNTAX_ERROR ("missing binary operator");
push_immediate:
want_value = false;
top->value = op.value; top->value = op.value;
top->unsignedp = op.unsignedp; top->unsignedp = op.unsignedp;
top->flags |= HAVE_VALUE;
continue; continue;
case CPP_EOF: prio = FORCE_REDUCE_PRIO; break;
case CPP_NOT: case CPP_NOT:
saw_leading_not = lex_count == 1; saw_leading_not = lex_count == 1;
prio = op_to_prio[op.op];
break; break;
case CPP_PLUS: case CPP_PLUS:
case CPP_MINUS: prio = PLUS_PRIO; if (top->flags & HAVE_VALUE) break; if (want_value)
/* else unary; fall through */ op.op = CPP_UPLUS;
default: prio = op_to_prio[op.op]; break; break;
case CPP_MINUS:
if (want_value)
op.op = CPP_UMINUS;
break;
default:
break;
} }
/* Separate the operator's code into priority and flags. */ flags = EXTRACT_FLAGS (op_to_prio[op.op]);
flags = EXTRACT_FLAGS(prio); prio = EXTRACT_PRIO (op_to_prio[op.op]);
prio = EXTRACT_PRIO(prio); if (prio == EXTRACT_PRIO (OPEN_PAREN_PRIO))
if (prio == EXTRACT_PRIO(OPEN_PAREN_PRIO))
goto skip_reduction; goto skip_reduction;
/* Check for reductions. Then push the operator. */ /* Check for reductions. Then push the operator. */
...@@ -645,13 +648,15 @@ _cpp_parse_expr (pfile) ...@@ -645,13 +648,15 @@ _cpp_parse_expr (pfile)
/* Most operators that can appear on the stack require a /* Most operators that can appear on the stack require a
right operand. Check this before trying to reduce. */ right operand. Check this before trying to reduce. */
if ((top->flags & (HAVE_VALUE | NO_R_OPERAND)) == 0) if (want_value)
{ {
if (top->op == CPP_OPEN_PAREN) if (top->op == CPP_OPEN_PAREN)
SYNTAX_ERROR ("void expression between '(' and ')'"); SYNTAX_ERROR ("void expression between '(' and ')'");
else else if (top->op != CPP_EOF)
SYNTAX_ERROR2 ("operator '%s' has no right operand", SYNTAX_ERROR2 ("operator '%s' has no right operand",
op_as_text (pfile, top->op)); op_as_text (pfile, top->op));
else if (op.op != CPP_CLOSE_PAREN)
SYNTAX_ERROR ("#if with no expression");
} }
unsigned2 = top->unsignedp, v2 = top->value; unsigned2 = top->unsignedp, v2 = top->value;
...@@ -682,44 +687,35 @@ _cpp_parse_expr (pfile) ...@@ -682,44 +687,35 @@ _cpp_parse_expr (pfile)
case CPP_MIN: MINMAX(<); break; case CPP_MIN: MINMAX(<); break;
case CPP_MAX: MINMAX(>); break; case CPP_MAX: MINMAX(>); break;
case CPP_UPLUS:
/* Can't use UNARY(+) because K+R C did not have unary
plus. Can't use UNARY() because some compilers object
to the empty argument. */
top->value = v2;
top->unsignedp = unsigned2;
if (CPP_WTRADITIONAL (pfile))
cpp_error (pfile, DL_WARNING,
"traditional C rejects the unary plus operator");
break;
case CPP_UMINUS:
UNARY(-);
if (!skip_evaluation && (top->value & v2) < 0 && !unsigned2)
integer_overflow (pfile);
break;
case CPP_PLUS: case CPP_PLUS:
if (!(top->flags & HAVE_VALUE)) top->value = v1 + v2;
{ top->unsignedp = unsigned1 | unsigned2;
/* Can't use UNARY(+) because K+R C did not have unary if (! top->unsignedp && ! skip_evaluation
plus. Can't use UNARY() because some compilers object && ! possible_sum_sign (v1, v2, top->value))
to the empty argument. */ integer_overflow (pfile);
top->value = v2;
top->unsignedp = unsigned2;
top->flags |= HAVE_VALUE;
if (CPP_WTRADITIONAL (pfile))
cpp_error (pfile, DL_WARNING,
"traditional C rejects the unary plus operator");
}
else
{
top->value = v1 + v2;
top->unsignedp = unsigned1 | unsigned2;
if (! top->unsignedp && ! skip_evaluation
&& ! possible_sum_sign (v1, v2, top->value))
integer_overflow (pfile);
}
break; break;
case CPP_MINUS: case CPP_MINUS:
if (!(top->flags & HAVE_VALUE)) top->value = v1 - v2;
{ top->unsignedp = unsigned1 | unsigned2;
UNARY(-); if (! top->unsignedp && ! skip_evaluation
if (!skip_evaluation && (top->value & v2) < 0 && !unsigned2) && ! possible_sum_sign (top->value, v2, v1))
integer_overflow (pfile); integer_overflow (pfile);
}
else
{ /* Binary '-' */
top->value = v1 - v2;
top->unsignedp = unsigned1 | unsigned2;
if (! top->unsignedp && ! skip_evaluation
&& ! possible_sum_sign (top->value, v2, v1))
integer_overflow (pfile);
}
break; break;
case CPP_MULT: case CPP_MULT:
top->unsignedp = unsigned1 | unsigned2; top->unsignedp = unsigned1 | unsigned2;
...@@ -821,16 +817,17 @@ _cpp_parse_expr (pfile) ...@@ -821,16 +817,17 @@ _cpp_parse_expr (pfile)
/* Check we have a left operand iff we need one. */ /* Check we have a left operand iff we need one. */
if (flags & NO_L_OPERAND) if (flags & NO_L_OPERAND)
{ {
if (top->flags & HAVE_VALUE) if (!want_value)
SYNTAX_ERROR2 ("missing binary operator before '%s'", SYNTAX_ERROR2 ("missing binary operator before '%s'",
op_as_text (pfile, op.op)); op_as_text (pfile, op.op));
} }
else else
{ {
if (!(top->flags & HAVE_VALUE)) if (want_value)
SYNTAX_ERROR2 ("operator '%s' has no left operand", SYNTAX_ERROR2 ("operator '%s' has no left operand",
op_as_text (pfile, op.op)); op_as_text (pfile, op.op));
} }
want_value = true;
/* Check for and handle stack overflow. */ /* Check for and handle stack overflow. */
top++; top++;
...@@ -868,11 +865,6 @@ _cpp_parse_expr (pfile) ...@@ -868,11 +865,6 @@ _cpp_parse_expr (pfile)
if (top != stack) if (top != stack)
{ {
cpp_error (pfile, DL_ICE, "unbalanced stack in #if"); cpp_error (pfile, DL_ICE, "unbalanced stack in #if");
goto syntax_error;
}
else if (!(top[1].flags & HAVE_VALUE))
{
SYNTAX_ERROR ("#if with no expression");
syntax_error: syntax_error:
result = 0; /* Return 0 on syntax error. */ result = 0; /* Return 0 on syntax error. */
} }
...@@ -891,6 +883,11 @@ op_as_text (pfile, op) ...@@ -891,6 +883,11 @@ op_as_text (pfile, op)
{ {
cpp_token token; cpp_token token;
if (op == CPP_UPLUS)
op = CPP_PLUS;
else if (op == CPP_UMINUS)
op = CPP_MINUS;
token.type = op; token.type = op;
token.flags = 0; token.flags = 0;
return cpp_token_as_text (pfile, &token); return cpp_token_as_text (pfile, &token);
......
gcc/cpplib.h
...@@ -46,9 +46,9 @@ typedef struct cpp_callbacks cpp_callbacks; ...@@ -46,9 +46,9 @@ typedef struct cpp_callbacks cpp_callbacks;
struct answer; struct answer;
struct file_name_map_list; struct file_name_map_list;
/* The first two groups, apart from '=', can appear in preprocessor /* The first three groups, apart from '=', can appear in preprocessor
expressions. This allows a lookup table to be implemented in expressions (+= and -= are used to indicate unary + and - resp.).
_cpp_parse_expr. This allows a lookup table to be implemented in _cpp_parse_expr.
The first group, to CPP_LAST_EQ, can be immediately followed by an The first group, to CPP_LAST_EQ, can be immediately followed by an
'='. The lexer needs operators ending in '=', like ">>=", to be in '='. The lexer needs operators ending in '=', like ">>=", to be in
...@@ -58,6 +58,7 @@ struct file_name_map_list; ...@@ -58,6 +58,7 @@ struct file_name_map_list;
#define CPP_LAST_EQ CPP_MAX #define CPP_LAST_EQ CPP_MAX
#define CPP_FIRST_DIGRAPH CPP_HASH #define CPP_FIRST_DIGRAPH CPP_HASH
#define CPP_LAST_PUNCTUATOR CPP_DOT_STAR #define CPP_LAST_PUNCTUATOR CPP_DOT_STAR
#define CPP_LAST_CPP_OP CPP_EOF
#define TTYPE_TABLE \ #define TTYPE_TABLE \
OP(CPP_EQ = 0, "=") \ OP(CPP_EQ = 0, "=") \
...@@ -90,8 +91,11 @@ struct file_name_map_list; ...@@ -90,8 +91,11 @@ struct file_name_map_list;
OP(CPP_GREATER_EQ, ">=") \ OP(CPP_GREATER_EQ, ">=") \
OP(CPP_LESS_EQ, "<=") \ OP(CPP_LESS_EQ, "<=") \
\ \
/* These 3 are special in preprocessor expressions. */ \
TK(CPP_EOF, SPELL_NONE) \
OP(CPP_PLUS_EQ, "+=") /* math */ \ OP(CPP_PLUS_EQ, "+=") /* math */ \
OP(CPP_MINUS_EQ, "-=") \ OP(CPP_MINUS_EQ, "-=") \
\
OP(CPP_MULT_EQ, "*=") \ OP(CPP_MULT_EQ, "*=") \
OP(CPP_DIV_EQ, "/=") \ OP(CPP_DIV_EQ, "/=") \
OP(CPP_MOD_EQ, "%=") \ OP(CPP_MOD_EQ, "%=") \
...@@ -135,8 +139,7 @@ struct file_name_map_list; ...@@ -135,8 +139,7 @@ struct file_name_map_list;
TK(CPP_COMMENT, SPELL_NUMBER) /* Only if output comments. */ \ TK(CPP_COMMENT, SPELL_NUMBER) /* Only if output comments. */ \
/* SPELL_NUMBER happens to DTRT. */ \ /* SPELL_NUMBER happens to DTRT. */ \
TK(CPP_MACRO_ARG, SPELL_NONE) /* Macro argument. */ \ TK(CPP_MACRO_ARG, SPELL_NONE) /* Macro argument. */ \
TK(CPP_PADDING, SPELL_NONE) /* Whitespace for cpp0. */ \ TK(CPP_PADDING, SPELL_NONE) /* Whitespace for cpp0. */
TK(CPP_EOF, SPELL_NONE) /* End of line or file. */
#define OP(e, s) e, #define OP(e, s) e,
#define TK(e, s) e, #define TK(e, s) e,
......
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